CVE-2019-3978: MikroTik RouterOS

High severity, CVSS 7.5. EPSS: 10.3% chance of exploitation in the next 30 days.

RouterOS versions 6.45.6 Stable, 6.44.5 Long-term, and below allow remote unauthenticated attackers to trigger DNS queries via port 8291. The queries are sent from the router to a server of the attacker's choice. The DNS responses are cached by the router, potentially resulting in cache poisoning

Affected products

• MikroTik RouterOS: up to and including 6.44.5; up to and including 6.45.6

Published 2019-10-29. Last modified 2026-06-17.